If in triangle XYZ, XY = XZ and M, N are the mid points of XY, YZ, then which one of the following is correct?

If in triangle XYZ, XY = XZ and M, N are the mid points of XY, YZ, the

1.	If in triangle XYZ, XY = XZ and M, N are the mid points of XY, YZ, then which one of the following is correct?
A.	MN = YZ
B.	NY = NZ = MN
C.	MX = MY = NY
D.	MN = MX = MY
Answer» E.